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Why are animals used in NIH research?


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NIH is the steward of medical and behavioral research for the Nation. Its mission is science in pursuit of fundamental knowledge about the nature and behavior of living systems and the application of that knowledge to extend healthy life and reduce the burdens of illness and disability.

NIH-supported scientists study diseases that cause pain and suffering and threaten the quality and length of life. NIH-supported scientists also study basic biological processes, expanding our knowledge of the origins and causes of disease. Through such research involving both humans and animals, scientists identify new ways to treat illnesses, extend life, and improve health and well-being.

Both people and animals have unique and important roles as research subjects. Many medical advances that enhance the lives of both humans and animals originate from animal studies. The types of animals used in research are chosen for their similarity to humans in anatomy, physiology, and/or genetics. Not only can we learn how to prevent, treat, and cure human diseases by studying animals, but often the treatments developed can also be used to improve the health of animals.

When new thinking about diseases and treatments are developed from this research, they must be evaluated very carefully so that benefits and risks from the proposed approach are clear. When necessary, new hypotheses are tested in animals first in order to gather sufficient evidence of these benefits and risks before considering possible use in humans.

We can study animals in ways that we cannot study people for many reasons. Animal studies conducted in the laboratory allow scientists to control factors that might affect the outcome of the experiments—factors like temperature, humidity, light, diet, or medications. Even the genetic composition of many animal models can be known and understood completely. These rigorous controls allow for more precise understanding of biological factors at hand and provide greater certainty about experimental outcomes when developing treatments. Additionally, the experimental integrity of the research is dependent upon a well-cared-for animal.  In fact, good animal care and good science go hand in hand.

ArrowHow does the NIH ensure their welfare?